Background: Gut microbiome could have central role in development of type 1 and type 2 diabetes mellitus (T1D) & (T2D). Objectives: The aim of the present study is to detect the composition of gut microbiota among T1D and T2D patients compared to healthy individuals. Methodology: The intestinal microbial composition of diabetic and heathy groups was investigated by both traditional culture techniques and polymerase chain reactions with amplification of the 16-23S rRNA intergenic spacer (IS) region. Results: By applying culture, diabetic groups showed a non-significant higher Firmicutes/ Bacteroidetes ratio (4.7% in T1D and 9% in T2D) compared to control group (4%) P value is 0.2058. While, PCR method showed that the diabetic group had a non-significant higher percentage of Lactobacillus spp., Faecalibacterium prausnitzii, Alistipes spp., Bacteroides thetaiotaomicron and Akkermansia muciniphila compared to healthy group (P value=0.407). Conclusion: Both diabetic groups showed a non-significant Firmicutes/Bacteroidetes ratio compared to control group by both culture and PCR techniques.